Surface dressing machine



Aug. 4, 1936. F. E. WOODWARD SURFACE DRESSING MACHINE Filed Oct. 22, 1934 2 Sheets-Sheet 2 INVENTOR film/Vivi: Mom/A120 ATTORNE i atenteti Aug. 4, 1936 'uuirso s'mrss SURFACE DRESSING MACHINE I Frank E. Woodward, Rochester, N. Y. Application October .22, 1934', :Serial No. 749,383

12 Claims. (01. 51-180) This invention relates to surface dressing machines for finishing ceilings, walls and .floors poured of concrete or stone composition and one of the objects of "this invention is to providea machine which will do the work elficiently and quickly with a minimum amount of .laboron the part of the operator of the machine.

.Another object of this invention is to so construct the machine that it can be quickly and easily adjusted to perform its finishing operation on the ceiling, the side walls and the floor.

A further object of this invention is; to provide the machine with a novel form of grinding head.

All these and other objects of the invention will become more readily apparent from the detailed description thereof which follows, reference being bad to the accompanying drawings .in which Figure 1 is a top plan viewof the machine.

Figure .2 is a side elevation thereof with a portion of the grinding head'illustrated in sec .tion.

:Figure 3 is a horizontal sectional view'taken 1.0-1'l'ith9 line Bar-3m of Figure 2.

Figure 4 is a horizontal sectional .view taken on the line iz-4m of Figure 2.

Figure 4A is a sectional view taken on the line. 4xt:r of Figure 2 showing a modified conistruction in which the tie bolt I2 is replaced by a short bolt i 2A.

Figure 5 is a horizontal sectional view taken on the line Bar-5a: of Figure 2.

Figure 6 is a horizontal sectional view taken on the line 6a:6x of Figure 2.

Figure '7 is a vertical sectional view takenon the line lac-la: of Figure 2.

Figure 8 is a detail side elevation of the drive .for the machine.

In the several figures of the drawings-like reference numerals indicate like parts.

The surface dressing machine forming the subject matter of my presentinvention is-mount- --ed on 'a suitable chassis l which is supported at the forward end by two pairs of driving wheels 2, 2 and 3, 3. 'These wheels and their axles are oushioned by the springs 4 and 5 so that the chassis can yield when a downward pressure is exerted against it during the grinding operation of the machine. Therear of the chassis i is supported by a pair of casters 6, 6 which are suitably mounted one behind the other on the underside thereof. 7

On the chassis-near the front thereof are supported two vertically arranged. channel shaped uprights land 8 and in'theseuprights are ad- "justably mounted the tubular extensions '9 and Fit. For this purpose the channel shaped nup- .rights are provided each with a Vertical slot l as illustrated in Figure 2, .and thru theseslots 5 and a suitable hole provided in .one side and a slot it provided in theopposite side of each of "located the clamping plates il so that by threading the clamping'nuts l8 against these plates the extensions 9 and l are firmly clamped into the channel side of the uprights. The extensions 9 and i!) may thus be adjustably clamped to the uprights 'at any desired'elevation thereon.

Between the upperends of the extensions 9 and H] is adjustably supported the substantially semi-cylindrical supporting base 99. This baseis provided with vertical legs l 9A, 19A which depend from the base between the extensions'Q and'l'll and are clamped thereto by means-of the clamping bolts 2, 26 which draw the semicylindrical clamping members ZiiA against the inside wall and'the legs ISA, ISA against the outside wall of the extensions 9 and "Hi as illustrated in Figure 3. In this way the base i9 is adjustably mounted on the extensions 9 and iii and may be supported thereon at any desired elevation.

Whenthe surface dressing machine is used for finishing floors, not only the extensions 9 and "ill must be lowered within the uprights l 'and 8 but the base l9 must also belowered withint'he extensions 9 and It. Inthis case the long tie bolts l2 and H) which fasten the extension to the uprights are replaced by short clamping bolts I2A so that the clamping members 28A 5 within the extensions 9 and l can'slide past the clamping members l4 and make the adjustment possible.

Inthecenter of the semicylindrical base I9 is provided the vertical bearing 2! for the. upper end of the collapsible shaft 22. This shaft, as illustrated in Figure 2, is :made up of three sections which are telescopically connected with each otherand are driven by the bevel gear 23 from the bevel pinion 23A. The latter is mounted 5 on the drive shaft 24 which is connected to the motor shaft 25 by means of the coupling or friction clutch 26. The motor 21 thus operates to drive the collapsible shaft 22 to rotate the bevel pinion 28 which in turn transmits its motion to the bevel gear 29 carried on the horizontal shaft 30. The latter is suitably journaled in the swivel head 3| which is supported on the base l9 and is adapted to swing on the shaft 22 as its pivot. Notches 32, 32 provided in the periphery of the base l9 are adapted to receive a locking bolt 33 carried by the swivel head and thus hold the swivel head in either a forwardly or sidewardly pointing direction.

The swivel head 3! carries the vertical face plate 34 on which is rotatably mounted the face plate 35 carried by the grinding head 36. Clamping bolts 31 are used to clamp the two face plates together in order to lock the grinding head to the swivel head after the desired rotary adjustment of the head has been made. The horizontal shaft 30 serves as the pivot onwhich the grinding head can turn on the swivel head. Shaft 38 has keyed thereto the bevel pinion 38 which is adapted to mesh with the bevel gear 39 which is splined to the vertical drive shaft 40 of the grinding head. The latter shaft extends into the gear box 4! where a pinion 42 is keyed to the shaft and meshes with the gears 43, 44, 45 and 46 to cause. them to simultaneously rotate the shafts 41, 48, 49 and 50 which are splined to the gears and carry at their upper end the grindstone holders 5!, 5|.

The grindstone holders have a limited rocking motion on the ends of the shafts 41, 48, 49 and 5B and each of them is provided with a horizontal channel 52 in which the grindstones 53 and 54 are clamped in place by the bolt operated clamping Wedges 55 which engage the side of a grindstone and hold these stones with their upper portion projecting out of the channel of the holder. The grindstone holders are arranged so that in one position they are located at right angles to each other so as to retain a relative position to each other during their rotation. A rod 56 is carried by and depends from the gear box so as to engage the fixed'portion of the grinder head and keep the gear box from rotating during the rotation of the individual grindstone holders.

The shafts which carry the grindstone holdas project thru the gear box and at their lower end are provided with a suitable thrust hearing so as to permit the engagement of a spring 51 therewith'and yieldingly support the shaft with its grindstone holder. The springs 51 are carried by the levers 58 which in turn are held in place by a latch 59. When it is desired to withdraw the. spring support from any one or more of the grindstone holders the latch 59 is disengaged from the lever 58 so as to reduce or entirely eliminate the spring pressure of the spring 51 against its shaft.

In addition to the spring pressure exerted on each grindstone holder by the springs 51 further spring pressure is simultaneously exerted against all of the grindstone holders by means of the. compression of the spring 60 which surrounds the vertical drive shaft 40 and is interposed between the antifriction thrust bearing GI and the outer end of the lever arm 62. This arm is suitably mounted on the grinder head 36 so that by forcing down the handle end thereof the free end compresses the spring 63 and yieldingly forces the shaft 40 with its grindstone holders upward. in addition to the controllable pressure exertable by the grindstones against the surface to be finished a normal pressure is automatically exerted by the springs which yieldingly support the chassis on the wheels 2, 2 and 3, 3 during 5 the grinding operation.

Fastened to each side of the gear box 4! is a splash guard 63 and on the gear box within these guards are mounted a series of sprinkler heads 64 which are suitably connected to a water supply which furnishes water under pressure. Water sprays are thus directed against the. surface over which the grindstones operate and the splash guards keep the water mixed with the stone ground from the surface from splashing from the grinder head.

For the purposeof raising and lowering the grinder head in order to adjust it to various heights, a screw 65 is used. One end of this screw is mounted to rotate in a suitable bearing 0 in the chassis of the machine and the other end is threaded into the stationary sleeve 66. The screw carries a friction wheel 67 and the drive shaft 22 carries the friction wheel 38. To rotate the screw by means of the friction wheel 68 in 25 one direction, the idler friction wheel 69 is brought in contact with both the friction wheels 68 and 67 and to rotate the screw in the opposite direction the idler friction wheel Ill is brought in frictional contact with the friction wheel 68 30 and the friction wheel 7! which in turn is in frictional contact with the friction wheel 61 of the screw. The screw may thus be rotated to raise and lower the grinder head by manipulating the handle 12 to bring the various friction 35 wheels in engagement with each other as above described.

To move the machine while the grinding of a surface by the grindstones is in progress or when it is desired to move the machine from one location to another, the wheels 2 and 3 are positively driven by means of the worm wheels 13 and 14 carried by the wheel shafts. These worm wheels mesh with the worms 15 and '16 which are splined to the drive shaft 11. To this shaft is connected an extension l8 by means of the flexible coupling 19 and this extension carries the friction wheel 80. This friction wheel is adapted to be brought into frictional contact with the periphery of either the coupling 24 driven by the motor shaft 25, or the idler friction pulley 8i mounted alongside the coupling 24 and in constant frictional contact therewith. For this purpose the extension shaft 78 passes thru a cam slot bearing 82 provided in the support 83 and thru the vertical slot 84 provided in the lever 85 so that when this lever is moved in one direction the extension shaft is simultaneously shifted and raised to have the friction wheel 80 make contact with the coupling 24 ,to be rotated in one direction and when the 60 lever is moved in the opposite direction the extension shaft is shifted and raised to have the friction wheel 83 make contact with the idler pulley BI and be rotated thereby in the opposite direction. The wheels are thus driven forward 65 or back at will by simply shifting the lever 85 in either one or the other direction as above described. In order to keep the friction wheels in driving contact after they have been brought in contact with each other, a spring 86 is suitably connected between the end of the extension shaft 18 and the motor so that this spring will hold the friction wheel yieldingly in contact with-either the coupling 24 or the idler friction wheel 8]. A concaved seat 81 provided'in the middle'of the cam slotrbearing will hold the extension shaft in to remain stationary during the grinding operation.

Toprevent a breaking of the driving mechanismshould the grinder head strike an obstruction in the movement of the machine, the wheel axles which carry the driving wheels 2 and 3 are mounted in an elongated opening which permits theseaxles to slightly move forward with thewheels. while the chassis is held stationary by the contact of the grinder head with an obstruction. This slight forward movement then gives the operatorsufiicient time to stop the movement of the machine. by disengaging the friction wheel iidfrom either the coupling 2d or the idle friction pulley 81 before the damage is done in the driving mechanism. For this reason the worms i5 and it are splined'to the shaft if to permit them to shift with the worm wheels when the latter are carried forward with the wheel shafts after the chassis is stopped.

From the foregoing it will be apparent that the construction of the machine permits a vertical adjustment of the grinder head first by vertically adjusting the tubular extensions 9 and it) in the channel shaped uprights l and 8, second by vertically adjusting the supporting base HQ between the vertical extensions 9 and id and third by raising the shaft 48 to elevate the gear box which supports and drives the individual grinds-tone holders. The latter adjustment is made possible by the extra length of the shaft 40 and the pins 88 which are located at spaced intervals on the shaft and provide shoulders against which the antifriction thrust bearing at is placed to support the shaft by means of the expansion spring 50.

The lateral adjustment is secured by rotating the swivel head M on the base l9 and looking it thereto to have the grinder head project either to one side or the other or to the front of the machine. This latter adjustment is supplemented by the rotation of the grinder head on the swivel base and looking it thereto to have the grindstone holder projecteither upwardly to finish a ceiling, sidewardly to finish a wall or downwardly to finish a floor. Some of these adjustments are also necessary when it is desired to finish the sides and the bottom of a beam and the surface between the beams.

When finishing a ceiling the machine is placed on a scaffolding especially put up for this purpose or used by the workmen who do other construction work. The planks which provide the floor of the scaffolding are sometimes separated and to prevent the supporting wheels of the machine from dropping into the cracks between the planks during the movement of the chassis the two pairs of driving wheels and the two casters are used and arranged behind each other so that when one wheel or one caster is located over a crack in the floor the other will support the chassis on the plank to one side or the other of the crack in the scaffold.

For this same reason the front wheels 2, 2 and 3, 3 are staggered with relation to each other as illustrated in Figure l in which the wheels 2, 2 are shown located outside of the wheels 3, 3 so as to support the chassis even if one or the other should be located over a longitudinal crack in the fioor of the scaffolding.

I-claim: n

1..A surfacedressing machine comprising a, pair of fixed uprights, a pair of extensions adjustably mounted on said uprights, a base supported by said extensions, and a supporting head rotatably adjustable in vertical plane on said base, a non-rotating grinder head radially mov able on. said supporting head and grinding members mounted to rotate on said grinder head.

A surface dressing machine comprising a chassis, uprights mounted on said chassis, a supporting head rotatably mounted in a vertical plane on said uprights, a non-rotating grinder head radially movable on said supporting head and a plurality of grindstone holders projecting from and mounted to rotate on said grinder head.

3. A surface dressing machine comprising a chassis having driving wheels yieldably supporting' said chassis on said driving wheels, uprights mounted on said chassis, a supporting head rotatably supported on said uprights in a vertical plane, a non-rotating grinder head radially movable on said supporting head, a plurality of grindstone holders mounted to rotate on said grinder head and yielding means for individually supporting said grindstone holders on said grinder head. I

4. A surface dressing machine as set forth in claim 3 including means for yieldingly supporting said grinder head on said supporting head and means for moving said grinder head and its yielding support.

5. A surface dressing machine comprising a chassis, supporting uprights mounted thereon, a supporting head vertically adjustable on said uprights, a grinder head rotatable in a vertical plane on said supporting head, a plurality of grindstones mounted to individually rotate on said grinder head, a motor carried on said chassis and collapsible driving means connecting said motor with said grindstones to rotate said grindstones with the grinder head located at any elevation and angular position on said uprights.

6. A surface dressing machine comprising a chassis, an axle carried by said chassis and mounted to yield in the direction of its movement, driving wheels carried by said axle to support said chassis, a grinder head supported on said chassis and driving means for operating said grinder head and driving said driving wheels.

7. A grinder head for surface dressing machines comprising a gear box, a plurality of gears mounted in said gear box, a pinion for simultaneously rotating said gears, a shaft splined in each of said gears, a grind stone holder carried by each of said shafts on top thereof, means for yieldingly supporting each shaft in an elevated position, means for releasing the yielding support of each of said shafts to cause their grindstone holders to drop to a lower position, and means for yieldingly supporting said gear box.

8. A surface dressing machine comprising a base, a vertically extensible frame mounted on said base, adjustably extensible bracing means between said frame and said base for holding said frame in any extended position on said base, a horizontal driving shaft journaled on said frame, a supporting head rotatably mounted on said frame concentric to said driving shaft, a grinder head supported by said supporting head and means provided on said supporting head for moving said grinder head radially to the axis of rotation of said supporting head.

9. In a surface dressing machinethe combina- 75 tion of a horizontal supporting base, a radially projecting supporting head rotatably mounted on said base, a vertically arranged face plate provided at the outer end of said supporting head, a. second supporting head rotatably mounted in a vertical plane on said face plate, a supporting bracket extending radially from said second supporting head to one side thereof and a non-rotating grinder head supported by said bracket so as to be radially movable in and out on said' second supporting head and grinding members mounted to rotate on said grinder head.

10. In a surface dressing machine the combination of a supporting head mounted to rotate in a vertical plane, a supporting bracket extending radially from said supporting head, a driving shaft mounted in said bracket and movable end- Wise therein, a grinder head supported on said shaft and movable therewith, means for holding said grinder head against rotation on said supporting head and grinding members operated by said shaft to rotate on said stationary grinder head.

11. In a surface dressing machine the combination of'a supporting head mounted to rotate in a vertical plane, a supporting bracket extending radially from said supporting head, a driving shaft mounted to rotate in said bracket and movable endwise therein, a grinder head supported on said shaft and movable therewith, means for holding said grinder head against rotation on said shaft, a plurality of shafts slidably and rotatably mounted in said grinder head and driven by said driving shaft, grinding members carried by said shafts and means for releasably supporting said grinding shafts to provide a grinding and non-grinding position for said grinding members on said grinder head.

12. In a surface dressing machine the combination as set forth in claim 11 including means for yieldingly supporting said driving shaft on its grinder head on said bracket and means operating against said yielding support to move said driving shaft endwise so as to yieldingly force said grinding members against a fixed surface.

FRANK E. WOODWARD. 

